MISC

Question 1

What is an RPI?

Answer 1

Basically, this clasp assembly consists of a mesio-occlusal rest with the minor connector placed into the mesiolingual embrasure, but not contacting the adjacent tooth (Figure 7-11, A). A distal guiding plane, extending from the marginal ridge to the junction of the middle and gingival thirds of the abutment

Question 2

current concept of bar clasp design that refers to the rest, proximal plate, and I-bar component parts of the clasp assembly

Answer 2

RPI

Question 3

contraindications for bar type cusps?

Answer 3

A, Severe buccal or lingual tilts of abutment teeth. B, Severe tissue undercuts. C, Shallow buccal or labial vestibules.

Question 4

RPA clasp vs. RPI?

Answer 4

RPA clasp, AKERS clasp, was developed to overcome some problems encountered with he RPI clasp

Question 5

advantage of RPI clasp

Answer 5

An important but seldom mentioned advantage of the RPI clasp is its avoidance of contact with the lingual surface of the’abutment tooth.

Question 6

what are the contraindications for using an RPI clasp?

Answer 6

insufficient vestibular depth that will not allow the I bar to be kept 3 mm away form the gingival margin (needed for protection)
tissue undercut below the abutment teeth is present, relief for the approach arm of the I bar may be so extensive that it is uncomfortable to the patient.
without extensive alterations, the RPI cannot be used

Question 7

why do you want the I bar to be 3 mm away from the gingival margin?

Answer 7

it’s for protection of the gingival margin

Question 8

what surface does the RPI clasp extend?

Answer 8

to do ditolingual surface to provide RECIPROCATION

Question 9

would RPA or RPI be more esthetic?

Answer 9

RPI likely

Question 10

what does RPA stand for?

Answer 10

rest, proximal plate, Akers clasp arm

Question 11

what parts of the RPA are similar to the RPI?

Answer 11

the mesial rest and proximal plate are IDENTICAL to the RPI

RP duh

Question 12

what is the major difference between RPA and RPI?

Answer 12

the RETENTIVE arm is what’s different.

Akers comes from superior part of proximal plate and extends around tooth to engage the mesial undercut

Question 13

With its mesial rest and special retentive arm design, it gives essentially the same kind of tooth release that the RPI clasp provides.

Answer 13

understand this concept